The technique used in the creation of visual hallucinations, or “visual cliff”, is one of the oldest in visual effects.
It is often applied to a wide range of scenes and often involves lighting, a computer model or even special effects, such as a water-splashing splash.
It was created by visual effects supervisor Tom Clark in the late 1990s, and it’s now used to create many effects in the industry.
And yet, it’s still not quite perfected.
And that’s partly because of the limitations of modern software, said Clark.
“Visual cliff is not really a tool for making the illusion believable, and is actually a tool to reduce the realism of the scene,” he said.
“That’s one of its limitations, because if you can get rid of the realism and get the illusion that the scene is not real, you can make a really impressive scene.”
Clark said he and his team had created visual cliffs on the set of Star Wars: Episode IV A New Hope, where a camera operator used the technique to create a series of flickering shadows that appeared to come from the back of a spaceship.
“The problem with this technique is it doesn’t actually work with all of the lighting you want to use, because it has to work on the camera’s perspective,” Clark said.
It wasn’t until his team made an improvement that the technique was adopted in the Star Wars franchise, Clark said, adding that it is now used for effects in more than 200 films.
“We did some really fun things with this, and people have asked us about it,” he explained.
“And I think it’s probably the best we’ve ever done.”
One of the biggest hurdles to being able to create visual cliffs is a lack of space to build it from.
“There’s so much space in the film, so it’s hard to find the right space,” Clark explained.
That’s why he and co-writer Dan Pinchbeck created a computer-generated environment in which a large screen and a large background were created.
“I had this idea that if we were going to create this, it had to be really big,” he recalled.
“It had to look really big.
And we’ve done a lot of computer-graphics work in the past, so I think that was something we wanted to do.”
The resulting image of the space station, which was used for a scene in Episode IV, is a lot bigger than what was originally in the script, Clark explained, but the computer created it using the same technique.
“Now that we’ve got the technology, we can create a much more detailed, very realistic environment that can be used to simulate the look of a ship in the sky,” he added.
“But the trick is, it doesn’s actually get very expensive, because we have to build this from scratch.”
To create the illusion of a massive space ship, the team built a mock-up of a real-world space station in order to simulate its size.
But it was difficult to create the look they wanted, so they went back to their original idea.
“Instead of building this from a blank canvas, we decided to use a real space station,” Clark told Mashable.
“Then, it was really hard to get it in the right place.
And the reason is we had to have the space stations, so we had a really big space station to work with, so you can’t just use an old computer model and get a very good look.”
In the final image, a large piece of the film’s space station is visible, but it looks very small compared to the rest of the movie.
Clark said the team used the same techniques to create more realistic scenes in the final film, and the effect is a bit more subtle than the first one.
“In the original film, the entire space station has to look big, and so we tried to do that in the movie as well,” he continued.
“This time, we did something slightly different.
We were trying to do a real piece of that space station.”
In this image, the camera has zoomed in on the space ship and the background.
It has also been rendered using a digital rendering technique, but that technique was only used for one scene.
“If we’re going to do it, we’re not going to make the spaceship look big and the crew look small,” Clark continued.
The trick is that we have the technology so we can make it from scratch.
“So instead of building a spaceship from scratch, we created a real spaceship and then built it from that,” he concluded.